seniorHadoop
What is Hadoop data serialization and Writable interface?
Updated May 16, 2026
Short answer
Writable is Hadoop’s serialization interface for efficient data transfer.
Deep explanation
Hadoop uses Writable instead of Java serialization for performance. It defines how objects are written to and read from data streams. Custom Writable classes improve efficiency in MapReduce communication.
Real-world example
Custom data types in large-scale log processing.
Common mistakes
- Using Java Serializable instead of Writable.
Follow-up questions
- Why Writable is faster?
- What is WritableComparable?